Excellent Leavening Agent Low in Fat Excellent Source of Protein and Calcium Mixes Easily for Rich, Creamy Taste Most professional bakers will tell you that buttermilk is a necessity for any kitchen. It’s acidic and reacts with alkaline baking soda to create carbon dioxide bubbles, which gives baked goods that signature light and fluffy texture. NOW Real Food Buttermilk Powder is superior to the liquid form since it has a long shelf life and doesn’t require refrigeration. Buttermilk is an excellent source of protein and calcium.